Ultrasonic sensor control system for occupancy sensing

• US 8,844,361 B2
• Filed: 07/27/2011
• Issued: 09/30/2014
• Est. Priority Date: 07/30/2010
• Status: Active Grant

• Current Assignee: The Watt Stopper Incorporated (Legrand SA)
• Original Assignee: The Watt Stopper Incorporated (Legrand SA)
• Inventors: Joyce, Jason
• Primary Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US13/191,673
• Publication Number:
  US 20120024069A1
• Time in Patent Office: 1,161 Days
• Field of Search: 736/32, 736/49, 340/541
• US Class Current: 73/632
• CPC Class Codes: G01N 29/34 Generating the ultrasonic, sonic or infrasonic waves , e.g. electronic circuits specially adapted therefor
• CPC Class Codes: G01S 15/04 Systems determining presence of a target
• CPC Class Codes: G01S 7/52004 Means for monitoring or calibrating short-range imaging G01S7/5205
• CPC Class Codes: H03K 17/94 characterised by the way in which the control signals are generated
• CPC Class Codes: H03K 2217/94005 activated by voice or sound

Abstract

An active ultrasonic room occupancy sensor with the output amplitude of the transmitter controlled by the amplitude of power applied to the transmitter to control the zone of coverage for a sensor. An adjustable voltage regulator under control of a microcontroller applies controlled amplitude voltage to the transmitter to adjust the output amplitude of the transmitter. The adjustable amplitude transmitter allows an occupancy sensor to have its total output energy adjusted to conform to the area to be covered. Lowering the total ultrasonic energy in the monitored space lowers the sensitivity of the receiver to inappropriate activations. Lowering the input power to the transmitter also lowers the total internal system noise and provides an improved signal to noise ratio in the receiver. Alternatively, the power applied to the receiver may also be controlled by an adjustable voltage regulator under control of the microcontroller to improve receiver efficiency.

Claims

1. An active ultrasonic occupancy sensor comprising:

an ultrasonic transmitter;

an ultrasonic receiver;

a power supply applying power to an adjustable voltage regulator which applies adjustable amplitude power to the ultrasonic transmitter;

a microcontroller controlling the ultrasonic transmitter and the ultrasonic receiver by controlling the amplitude of the output voltage of the adjustable regulator.

2. The active ultrasonic occupancy sensor of claim 1 wherein the power from the power supply has a voltage of about 24VDC and the adjustable voltage regulator provides adjustable power with a voltage in the range of 5-9VDC.

3. The active ultrasonic occupancy sensor of claim 1 further comprising:

a fixed voltage regulator which receives power from the power supply and applies power to the adjustable voltage regulator.

4. The active ultrasonic occupancy sensor of claim 3 wherein the fixed voltage regulator applies power to the adjustable voltage regulator with a voltage of 12VDC.

5. An active ultrasonic occupancy sensor comprising:

an ultrasonic transmitter;

an ultrasonic receiver;

a power supply applying power to an adjustable voltage regulator which applies adjustable amplitude power to the ultrasonic receiver;

a microcontroller controlling the ultrasonic transmitter and the ultrasonic receiver by controlling the amplitude of the output voltage of the adjustable regulator.

6. The active ultrasonic occupancy sensor of claim 5 wherein the power from the power supply has a voltage of about 24VDC and the adjustable voltage regulator provides adjustable power with a voltage in the range of 5-9VDC.

7. The active ultrasonic occupancy sensor of claim 5 further comprising:

a fixed voltage regulator which receives power from the power supply and applies power to the adjustable voltage regulator.

8. The active ultrasonic occupancy sensor of claim 7 wherein the fixed voltage regulator applies power to the adjustable voltage regulator with a voltage of 12VDC.

9. An active ultrasonic occupancy sensor comprising:

an ultrasonic transmitter;

an ultrasonic receiver;

a power supply applying power to an adjustable voltage regulator which applies adjustable amplitude power to the ultrasonic transmitter and the ultrasonic receiver;

a microcontroller controlling the range of the ultrasonic transmitter and the sensitivity of the ultrasonic receiver by controlling the amplitude of the output voltage of the adjustable regulator.

10. The active ultrasonic occupancy sensor of claim 9 wherein the power from the power supply has a voltage of about 24VDC and the adjustable voltage regulator provides adjustable power with a voltage in the range of 5-9VDC.

11. The active ultrasonic occupancy sensor of claim 9 further comprising:

a fixed voltage regulator which receives power from the power supply and applies power to the adjustable voltage regulator.

12. The active ultrasonic occupancy sensor of claim 11 wherein the fixed voltage regulator applies power to the adjustable voltage regulator with a voltage of 12VDC.